Nipples

The 3 steps involved when a baby breastfeeds

When a baby drinks milk, the sucking motion is completely different from how an adult drinks through a straw. First the baby opens his mouth, spreading his lips outward, and presses them around the nipple (latching on). He then begins moving his tongue in a wave-like motion called peristaltic movement This squeezes the nipple and extracts milk (sucking). Finally, the base of the tongue moves strongly, channeling the milk into the esophagus (swallowing). These three steps work together to allow your baby to drink milk skillfully.
When feeding your baby from a bottle, it's vital that the natural sucking motions are faithfully reproduced.